Weeds, what are they good for?

What a great question. Rather than how do I get rid of (insert weed of choice) ask the question, what are weeds good for? What is this weed trying to tell us? When we are curious and ask better questions, we enable dynamic and critical thinking, uncovering richer, more relevant answers.

Scotch Thistle Flower

Wisdom from Grandpa Zerner

Growing up on our family dairy farm, my Grandpa Zerner would comment that when we had a lot of Scotch Thistles, the next season would be a good one. This is an interesting statement, and I wish I had the foresight to ask him more about this before he passed away. Was this his observations, or was this some family wisdom that had been passed down through the generations? What were the characteristics of a ‘good’ next season? Was the presence of ‘a lot’ of Scotch Thistles a correlation or causation to the current season, and/or to the next season? So many questions???

Using Scotch Thistles as an example let’s work through it.

·       We know that conditions continually change; moisture, temperature, wildlife populations, grazing management, other human interventions (cultivation, fertilization, spraying, chipping).

·       We know that on our dairy farm, even though conditions changed and the amount of grass we would grow (carrying capacity), we never changed the number of cows we milked. So, some years we had abundant pastures, and some years paddocks were flogged.

·       We know that Nature doesn’t like bare soil, she doesn’t like being exposed.

·       We know that the Scotch Thistle family is extremely spikey, that livestock tend to avoid individual plants, and that they also have a strong taproot.

·       We know that Nature will use the most appropriate plants at her disposal to improve the conditions of the ecosystem.

·       And we also know that in every square meter of soil there can be up to 50,000 weed seeds. Nature has a lot of choice!

Putting this all together, it could be that when we had drier years, we ended up with bare soil because we didn’t reduce the number of animals we had (animal demand was greater than feed supply). Therefore, Nature used the best plant she had available to protect the soil and reduce grazing pressure, i.e. Scotch Thistles. The Scotch Thistles were a physical barrier and protected over grazed pasture plants. Once the soil was covered again, there was no longer any reason for the Scotch Thistles to be around, so they finished their life cycle and disappeared. Job done!

What does a healthy pasture look like?

This can be a tricky question, and we don’t want to get it confused with, “What do we want our paddocks to look like?” I find that many people want to have an attractive farm, with nice even paddocks made up of their favourite grass and a scattering of legumes. Very few people want to have messy paddocks. Overall, people tend to want the picture postcard, the typical calendar shot farm. Unfortunately, this isn’t the same as a healthy pasture.

The challenge for us then is to go back to the original question- what does a healthy pasture look like?  Another way we can ask this is what percentage of grass versus legumes versus weeds does a healthy pasture have? Dr Judi Earl, an Australia Pasture Ecologist suggests a healthy pasture has a composition of 60-70% perennial grasses, 15-20% legumes and 10-15% forbs. (Note that forbs are another name for what most people call weeds). A healthy pasture will have some weeds!

Why does a healthy pasture have weeds?

Weeds add diversity and this is why it is the sixth RCS Grazing Principle: Maximise Biological Diversity. A healthy pasture has a healthy population of soil bugs. Soil bugs get their energy by feeding on the sugars that plants exude from their roots as a part of the photosynthesis process. In exchange for the sugars, soil bugs bring nutrients and moisture back to the plant. At certain times of the year, the only plants that are green and photosynthesising are weeds. Therefore, weeds are helping to maintain healthy populations of soil bugs which in return, help our grass and legumes grow.

A second key reason for having weeds in a healthy pasture is for animal health. Professor Fred Provenza has spent a lifetime researching what and why grazing animals eat what they do and has beautifully captured his observations in his book, Nourishment – What Animals Can Teach Us About Rediscovering Our Nutritional Wisdom.  The bulk of a grazing animal’s diet will be a small number of species, however if they have access to it, they will nibble at a huge number of species in a 24-hour period. This really shouldn’t be a surprise, because we have known for thousands of years the medicinal and nutritive value of plants. If in doubt, pick up any traditional, medicinal plant book, flip through the pages and note just about every weed you know has beneficial properties. Animals have nutritional wisdom and are able to self-medicate if they have access to a diverse suite of plants.

What are some ‘better’ questions in relation to weeds?

To remain curious about what weeds are trying to tell us, here are some more questions we can ask ourselves.

·       How has this paddock been managed over the past 6 weeks / 6 months / 6 years?

·       What season are we in? Summer? Winter?

·       What has the season been like? Wet? Dry? Hot? Cold?

·       What is the mineral balance of our soil? Are there deficiencies or excess of certain minerals?

·       What weed families have been present over time? Are they the same or are they changing?

·       Are our management practices continuously taking us back to bare ground?

These questions can act as prompts and may help explain why we have different flushes of weed at different times. What other questions could we ask?

When we run our I Bought A Farm Bootcamp, we dive further into balanced pastures and working with Nature.

On a final note.

I wonder what Grandpa Zerner would think now. We have changed our grazing management, are no longer dairying and in running a beef operation we are more easily able to adjust the number of animals we run based on the amount of grass we are growing. These changes all result in less bare soil and healthier pastures and ecosystem.

Nature is trying to talk to us through the expression of weeds. Can we pause, work out what she is trying to tell us, and then work with her? Just like I can’t ask Grandpa Zerner directly about his comment about Scotch Thistles, I can pause and think it through.

#HealthyPastures #HobbyFarms #RegenerativeAg #KnowledgeToPractice #IBoughtAFarm